When it became clear that other monarchs would not acquiesce in a
de facto partition of Bavaria, Joseph and his foreign minister,
Anton von Kaunitz, scoured the Habsburg realm for troops and concentrated six hundred guns and a 180,000–190,000-man Austrian army in Bohemia, Moravia, and Austrian Silesia. This amounted to most of Austria's two-hundred thousand effectives, leaving much of the
Habsburg border regions with the
Ottoman Empire under-guarded. On 6 April 1778 Frederick of Prussia established his army of eighty thousand men on the Prussian border with Bohemia, near
Neisse,
Schweidnitz, and the County of Glatz, At Glatz, Frederick completed his preparations for invasion: he gathered supplies, arranged a
line-of-march, brought up his artillery and drilled his soldiers. His younger brother,
Prince Henry, formed a second army of seventy-five to a hundred thousand men to the north and west, in Saxony. In April, Frederick and Joseph officially joined their armies in the field, and diplomatic negotiations ended. Wunsch withdrew; the next day, Nauendorf was promoted to major.
Invasion A few days after Wunsch's encounter with Nauendorf, Frederick entered Bohemia. His eighty thousand troops occupied Náchod but advanced no further. The Habsburg army stood on the heights of the
Elbe river, nominally under Joseph but with Count
Franz Moritz von Lacy in practical command. Lacy had served under Marshal
Daun during the Seven Years' War and knew his military business. He established the Austrian army on the most defensible position available: centered at
Jaroměř, a triple line of
redoubts extended southwest along the river to
Königgrätz. The Austrians also augmented this defensive line with their six hundred artillery pieces. includes most of 18th-century Bohemia. Joseph was outnumbered and nearly surrounded, but Frederick chose not to engage because of Joseph's superior position on the heights above the Elbe river. While the main Habsburg army faced Frederick at the Elbe, a smaller army under the command of Baron
Ernst Gideon von Laudon guarded the passes from Saxony and
Lusatia into Bohemia. Laudon was another battle-hardened and cagey commander with extensive field experience, but even he could not cover the long frontier completely. Shortly after Frederick crossed into Bohemia, Prince Henry, a brilliant strategist in his own right, maneuvered around Laudon's troops and entered Bohemia at
Hainspach. To avoid being flanked, Laudon withdrew across the
Iser river, but by mid-August, the main Austrian army was in danger of being outflanked by Henry on its left wing. At its center and right, it faced a well-disciplined army commanded by Frederick, arguably the best tactical general of the age and feared for his victories against France and Austria in the previous war. While his main army remained entrenched on the heights above the Elbe, Joseph encouraged raids against the Prussian troops. On 7 August 1778, with two squadrons of his regiment, the intrepid "rookie", now Major Nauendorf, led a raid against a Prussian convoy at
Bieberdorf in the County of Glatz. The surprised convoy surrendered and Nauendorf captured its officers, 110 men, 476 horses, 240 wagons of flour, and thirteen transport wagons. Soldiers later said they spent more time foraging for food than they did fighting. The armies remained in their encampments for the campaign season while men and horses ate all the provisions and forage for miles around. Frederick agreed. He laid plans to cross the Elbe and approach the Austrian force from the rear, but the more he examined the conditions of Joseph's entrenchments, the more he realized that the campaign was already lost. Even if he and Henry executed simultaneous attacks on the Königgrätz heights, such a plan exposed Henry to a flanking attack from Laudon. A coordinated frontal and rear assault was also unlikely to succeed. Even if it did, the Prussian losses would be unacceptable and would demolish his army's capacity to resist other invaders. From Frederick's perspective, the Russians and the Swedes were always ready to take advantage of any perceived Prussian weakness, and the French also could not be trusted to keep their distance. For Frederick, it was a risk not worth taking. Despite this realization, the four armies—two Austrian, two Prussian—remained in place until September, eating as much of the country's resources as they could. In his admiring history of Frederick the Great, the British historian
Thomas Carlyle relayed the story of Frederick and a Croatian marksman. As Frederick was reconnoitring, Carlyle maintained, the King encountered the Croat taking aim at him. Reportedly, he wagged his finger at the man, as if to say, "Do not do that." The Croat thought better of shooting the King, and disappeared into the woods; some reports maintain he actually knelt before the king and kissed his hand. Nauendorf continued his raids, the soldiers foraged for food and dug up the local potato crop, and Joseph and Frederick glared at one another by Königgrätz. Maria Theresa had sent Kaunitz on a secret mission to Berlin to offer a truce. In a second trip, she offered a settlement, and finally wrote to the Empress Catherine in Russia to ask for assistance. When Joseph discovered his mother's maneuvering behind his back, he furiously offered to abdicate. His mother enlisted the assistance she needed. Catherine offered to mediate the dispute; if her assistance was unacceptable, she was willing to send fifty thousand troops to augment the Prussian force, even though she disliked Frederick and her alliance with him was strictly defensive. Frederick withdrew portions of his force in mid-September. In October, Joseph withdrew most of his army to the Bohemian border and Frederick withdrew his remaining troops into Prussia. Two small forces of
hussars and
dragoons remained in Bohemia to provide a winter cordon; these forces allowed Joseph and Frederick to keep an eye on each other's troops while their diplomats negotiated at
Teschen. Klebeck led a column of Croats into the village. During the action, four hundred Prussians were killed, another four hundred made prisoner, and eight colors were captured. Following his successes against the Prussians in 1778, Joseph awarded Wurmser the Knight's Cross of the
Military Order of Maria Theresa on 21 October 1778. In another raid, on 1 January 1779, Colonel Franz Levenehr led 3,200 men (four battalions, six squadrons, and 16 artillery) into
Zuckmantel, a village in Silesia on the Prussian border, south of
Ziegenhals.
There he ran against a 10,000-man Prussian force commanded by General
Johann Jakob von Wunsch; the Austrians decisively defeated the Prussians, with a loss of 20 men (wounded) against the Prussian losses of 800. Two weeks later, Wurmser advanced into the County of Glatz in five columns, two of which, commanded by Major General
Franz Joseph, Count Kinsky, surrounded
Habelschwerdt on 17–18 January. While one column secured the approach, the other, under the leadership of Colonel Pallavicini, stormed the village and captured the
Landgrave of Hessen-Philippsthal, 37 officers, plus 700 to 1,000 men, three cannon and seven colors; in this action, the Prussians lost 400 men dead or wounded. Wurmser himself led the third column in an assault on the so-called Swedish blockhouse at
Oberschwedeldorf. It and the village of
Habelschwerdt were set on fire by
howitzers. Major General
Ludwig Terzy, who was covering with the remaining two columns, threw back the enemy support and took three hundred Prussian prisoners. Meanwhile, Wurmser maintained his position at the nearby villages of Rückerts and
Reinerz. On 3 March 1779, Nauendorf again raided Berbersdorf with a large force of infantry and hussars and captured the entire Prussian garrison. Joseph awarded him the Knight's Cross of the
Military Order of Maria Theresa (19 May 1779). ==Impact==